utils/node_modules/validator/lib/util/algorithms.js
2024-02-07 01:33:07 -05:00

101 lines
3.0 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.iso7064Check = iso7064Check;
exports.luhnCheck = luhnCheck;
exports.reverseMultiplyAndSum = reverseMultiplyAndSum;
exports.verhoeffCheck = verhoeffCheck;
/**
* Algorithmic validation functions
* May be used as is or implemented in the workflow of other validators.
*/
/*
* ISO 7064 validation function
* Called with a string of numbers (incl. check digit)
* to validate according to ISO 7064 (MOD 11, 10).
*/
function iso7064Check(str) {
var checkvalue = 10;
for (var i = 0; i < str.length - 1; i++) {
checkvalue = (parseInt(str[i], 10) + checkvalue) % 10 === 0 ? 10 * 2 % 11 : (parseInt(str[i], 10) + checkvalue) % 10 * 2 % 11;
}
checkvalue = checkvalue === 1 ? 0 : 11 - checkvalue;
return checkvalue === parseInt(str[10], 10);
}
/*
* Luhn (mod 10) validation function
* Called with a string of numbers (incl. check digit)
* to validate according to the Luhn algorithm.
*/
function luhnCheck(str) {
var checksum = 0;
var second = false;
for (var i = str.length - 1; i >= 0; i--) {
if (second) {
var product = parseInt(str[i], 10) * 2;
if (product > 9) {
// sum digits of product and add to checksum
checksum += product.toString().split('').map(function (a) {
return parseInt(a, 10);
}).reduce(function (a, b) {
return a + b;
}, 0);
} else {
checksum += product;
}
} else {
checksum += parseInt(str[i], 10);
}
second = !second;
}
return checksum % 10 === 0;
}
/*
* Reverse TIN multiplication and summation helper function
* Called with an array of single-digit integers and a base multiplier
* to calculate the sum of the digits multiplied in reverse.
* Normally used in variations of MOD 11 algorithmic checks.
*/
function reverseMultiplyAndSum(digits, base) {
var total = 0;
for (var i = 0; i < digits.length; i++) {
total += digits[i] * (base - i);
}
return total;
}
/*
* Verhoeff validation helper function
* Called with a string of numbers
* to validate according to the Verhoeff algorithm.
*/
function verhoeffCheck(str) {
var d_table = [[0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 0, 6, 7, 8, 9, 5], [2, 3, 4, 0, 1, 7, 8, 9, 5, 6], [3, 4, 0, 1, 2, 8, 9, 5, 6, 7], [4, 0, 1, 2, 3, 9, 5, 6, 7, 8], [5, 9, 8, 7, 6, 0, 4, 3, 2, 1], [6, 5, 9, 8, 7, 1, 0, 4, 3, 2], [7, 6, 5, 9, 8, 2, 1, 0, 4, 3], [8, 7, 6, 5, 9, 3, 2, 1, 0, 4], [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]];
var p_table = [[0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 5, 7, 6, 2, 8, 3, 0, 9, 4], [5, 8, 0, 3, 7, 9, 6, 1, 4, 2], [8, 9, 1, 6, 0, 4, 3, 5, 2, 7], [9, 4, 5, 3, 1, 2, 6, 8, 7, 0], [4, 2, 8, 6, 5, 7, 3, 9, 0, 1], [2, 7, 9, 3, 8, 0, 6, 4, 1, 5], [7, 0, 4, 6, 9, 1, 3, 2, 5, 8]]; // Copy (to prevent replacement) and reverse
var str_copy = str.split('').reverse().join('');
var checksum = 0;
for (var i = 0; i < str_copy.length; i++) {
checksum = d_table[checksum][p_table[i % 8][parseInt(str_copy[i], 10)]];
}
return checksum === 0;
}